Diagnostic apparatus



y5 Sheets-Shet 1 J. P. BUCKLEY DIAGNOSTIC APPARATUS Original Filed July 23, 1932 April is, 1937.

FIG. 9.

April 13, l937- J. P. BUCKLY` 2,077,211

DIAGNOSTIC ABPARATus Original Filed July 23. 1932 5 Sheets-Sheet 2 FXG. 2.

April 13, w3'7- k J. P. BucKLEY f 2,077,211

DIAGNOSTIC APPARATUS Original Filed July 23. 1932 5 Sheets-Sheet 5 he? M April i3, 1937- J. p. BUCKLEY 2,077,211

' DIAGNOSTIC APPARATUS Original Filed July 23. 1932 5 Sheets-Shea?. 4

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April 13, 1937. L.1. P. BUCKLEY DIAGNOSTIC 'APPARATUS 5 Sheets-Sheen'l 5 A Original Filed July.25, 1932.

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ooooooool 1 159 Llll lll ITIG` Patented Apr. 13, 1937 UNITED sTA'rE DIAGNOSTIC APPARATUS John P. Buckley, Washington, D. C.

Application July 23, 1932, Serial No. 624,270 Renewed October 29, 1935 12 Claims.

My invention relates broadly to diagnostic apparatus and more particularly to a method `and apparatus for automatically determining and recording the condition of the urine.

One of the objects of my invention is to provide an apparatus Which will diagnose disease discernible from the condition of the urine.

Another object of my invention is to provide a construction of test apparatus for automatically l0 determining the character of reaction between a uid under test and a reagent for determining therefrom the original condition of the fluid.

Still another object of my invention is to provide an automatic testing apparatus for iiuid having means for electrically indicating the specific gravity of the fluid and the reaction thereof with predetermined reagents.

A further object of my invention is to provide a mechanism operative in cycles to receive and determine the condition of a test fluid with means automatically operative subsequent to the conclusion of the test operation for flushing out the mechanism in a sanitary manner preparatory for a succeeding test observation.

A still further object of my invention is to provide a construction of test apparatus operative by means of coin control mechanism for initiating a cycle of observations in the testing of fluid Whose characteristics are to be determined.

Another object of my invention is to provide a fluid test apparatus operative to perform a multiplicity of successive observations upon a test fluid with means for registering the result of each observation and delivering a printed record of such observations.

Still another object of my invention is to provide a control circuit for a iiuid testing diagnostic apparatus in which an electron tube is'controlled by a light sensitive cell Which is acted upon at successive time intervals by light rays controlled by the specific gravity of the fluid under test and the reactions produced by reagents with the fluid under test.

A further object of my invention is to provide an electron tube control circuit operative by a light sensitive cell to control the functioning of a meter connected with the control circuit with connections from the meter for testing the conductivity of a test fluid for indicating the acidity thereof in combination With switchingT means for cyclically controlling the operation of the circuit for effecting a multiplicity of succeeding observations Wit'n respect to the test fluid.

Other and further objects of my invention re- (Cl. 23--253iV side in the method ofoperation the apparatus employed to carry out a multipliciof the diagnostic. apparatus of my invention and the structure of l ty of tests in cyclic order as will be more fully understood from the specification hereinafter following by reference to the accompanying drawings, wherein:

Figure 1 is a front elevational view of the apparatus of my invention With the casing and parts of Y the apparatus illustrated in cross-section; Fig. 2 is a sectional View taken on line 2--2 of Fig. 1; Fig. 3 is a front elevational view of the indicating meter employed in the apparatus of my invention; Fig. 4 is a diagrammatic view Vof the controll circuit employed inthe apparatus of my invention in association with the vsv'vitching mechanism which I provide for insuring the cyclic operation of the several tests performed by the apparatus of my invention; Fig. 5 is a detailed vieWl of one of the control cams which isemployed'for operating the indicatorl forinforming the operator as to the particular test being performed;

Fig, 6 is a view of the indicator controlled by-they cam mechanism of Fig. 5 for indicating the several tests as they arep'erformed in cyclic order Within the apparatus; Fig. 7 isa cross-sectional view through one of the delivery cups employed in the apparatus of my invention for predetermining the relative amounts of test fluid and reagent supplied to a test tube in the apparatus of my invention; Fig. 8 is a detailed view of the cam and valve actuator employed for controlling the flush water subsequent to the several test operations for cleaning the apparatus in a sanitary manner; Fig. 9 is a View of a modified form of optical system employed for electrically determining the nepheloidal, cloudy or turbid characteristic which may be produced by the. reagent with the test uid; Fig. 10 is a side elevation of a modied form of reagent introducing mechanism and illustrating the test tube and optical system in its relation to the reagent introducingy mechanism; Fig. 11 is a top plan View of the portion of the apparatus illustrated in Fig. 10; Fig. 12 is a cross-sectional View through the test tube showing a further modified form of optical system which may be employed in determining the lreactive condition by means of the rearrangement of light sensitive cell and light source for producing a reflective determination; Fig. 13 is a detailed view indicating the manner in which the `light source is controlled at the time that the reagent is introduced into the test fluid by means of lthe' apparatus of Figs. 10 and l1; Fig; 14; is adetailed view of the flushing valves in the test tube illustrating the manner in which sanitary condition of the apparatus may be insured after each observation; Fig 15 is a plan view of the printing attachment for recording the readings obtained by use of the apparatus of my invention; Fig. 16 is a side elevation of the printing attachment shown in Fig. 15; Fig. 17 is a view of the commutator used for controlling the printing operation; andl Fig. 18 is a viewof the report card delivered by the printing apparatus subsequent to each test observation.

I have described my invention in certain of its preferred embodiments by detailed reference to the drawings hereinafter. In explaining myinvention I have referred to the urine as the fluid under test. However there are chemical applications of the apparatus of my invention in other fields and I desire my invention to be considered in its broadest aspects and as applicable in many fields as set forth in the claims'hereinafter following.

The apparatus of my invention is mounted Within a casing indicated at I supported upon a base structure 2 vfrom which the various elements constituting the apparatus. are mounted. A rotatable drive shaft 3 is journaled within suitable standards 4 and 5 extending from base 2. The shaft 3 carries various operating cams which I have indicated in Fig. 1 at 6, l, 8, 9, I30, I3I, and I32 for actuating the several valves employed to control the admission of reagents to the fluid under f test and control the operation of the recording apparatus and the flushing operation Afor cleansing the vparts of thei apparatus. The

mechanism is drivenby an' induction motor such as anelectric clock -motor indicated at I3 which drives ashaft carrying worm gear I2 which meshes with the worm wheel YI I carried by shaft 3 for driving shaft 3 through periodic cycles effecting operation of the several instrumentalities which will be explained in more detail lhereinafter. Y Y

'I'he receiving container for the fluid under test is indicated at I connected lthrough discharge spout 34A to the test tube 33. Test tube 33provides a container for fluid under test delivered from the receiving container I and serves as a vessel in which the hydrometer 35 is mounted. The hydrometer 35 carries a shutter 36 on its extremity which is guided byplate 33 having guide members 38a thereon for permitting vertical movement of shutter 36 with respect to slot 39. The shutter 36 has .a graduated opening 31 therein which is shaped by the converging walls thereof to coact with slot 39 to allow a varying amount of light to pass from the light source 40 in housing 4I to the photoelectric cell inthe axially aligned casing 4I' along a beam indicated at 4I. The amount of light incident upon the photoelectric cell in casing 4I is directly proportional to the movement of the shutter 36 controlled by the position of the hydrometer 35 in the fluid under test in test tube 33. The amount of light incident upon the photoelectric cell in housing 4I' is, therefore, proportional to the specific gravity of the fluid under test in test tube 33.V

In order to determine the acidity of the fluid under test, I provide two electrodes 42 and 43 of dissimilar metals, one of which is electropositive and one of which is electromagnetic in the electrolyte constituted by the fluid under test. The electrodes 42 and 43 are mounted in the side Walls of the test tube which are electrically connected in the test circuit as represented more clearly in Fig. 4, for indicating on meter 92 the electromotive force across electrodes 42 and 43. The test tube 33 is mounted centrally with respect tothe apparatus and is connected through overflow tubes'44 and 45 leading from the sides of the test tube 33 to nozzles 46 and indirectly through reservoir 26 (Fig. 7) and overflow tube 26 to nozzle 47 which direct the fluid under test-into two symmetrically arranged smaller test tubes 48 and 49. Surrounding the smaller `test tubes, I provide heating coils 59 and 5I arranged to be connected in a heating circuit at a predetermined time interval in the cycle of operation of the apparatus. 'Ihe bottom of each of the test tubes 48 and 49 is provided with lenses 52 and' 53 and beneath these lenses I provide light sources 54 and 55 disposed in alignment with lenses 52 and 53 by means of housings 58 and 59. The light sources 54 and 55 are disposed in axial alignment with reflecting mirrors 56 and 5l with the lenses 52 and 53 and the fluid in test tubes 49 and 49 interposed in the optical pathv therebetween. The mirrors 56 and51 are supported on adjustable brackets which extend from the reservoirs I6 and I'I which `provide a mounting means for the electron tube apparatus employed in the test system of my invention. The reservoirs I8 and I'.' are mounted with respect to the casing I by suitable brackets 32 as illustrated more clearly in Fig. 2. The mirrors 56 and 51 are angularly adjusted to reflect the light beam transmitted through the fluid in test tubes 48 and 49 to the photoelectric cell in housing 4I. In lieu of the arrangement of the photoelectric cell in the position shown, I may provide individual photoelectric cells at I33 beneath each of lens 52 each test tube 48 and 49 for directing rays of.

light through the fluid in test tube 48, lens 52 and upon photoelectric cell |33.

Any overflow which may occur from test tubes 48 and 49 is deflected by means of deflecting protective collars 48d and 49a placed over the tube of each of the test tubes 48 and 49 for directing the overflow fluid into the basin 69. Basin 59 has a discharge orice and pipe connection 6I connected therewith for discharging the overflow fluid.

The reagent which is added to the fluid under test in each of the test tubes 48 and 45 is introduced into the fluid under test by any one of several methods. VIn Fig. l I have illustrated apparatus for introducing the reagent to the fluid under test by effecting the discharge of the reagent from reservoirs I4 and I5. Any suitable reagent may be employed to -effect the reaction with the iluid under test to produce a nepheloid characteristic or a cloudy or turbid effect 48 for occluding the passage of light in the optical systern provided through the test tubes. The reservoirs I 4 and I5 contain reagents of different characteristics for producing different reactionary effects with the fluid under test for obtaining ,readings of different characteristics. The determination of the character of the test is indicated to the observer from the front of the apparatus In this Cil housed within casing i by observing indicator l1 through aperture 8| in casing Indicator 9D on observing indicator Ti is moved behind apparatus 8| and are made visible to the observer from the front of the apparatus in the cyclic order in which the tests are automatically performed by the apparatus. These indications mayl be of various characteristics as illustrated by way of example in Fig. 6 where the character of the tests performed may be read as acid-alkali, spe'cic gravity, albumen and sugar.

The movement of the observing indicator is controlled by actuating rod 'i6 connected with lever 74 pivoted at 15 and tensioned by means of spring u so that the end of lever i4 is normally engaged by cam 8 on shaft 3. The movement of the observing indicator il is directly controlled by coin control mechanism by which the functioning of the apparatus is governed. The coin control mechanism is shown as including coin slot 58 through which 'coin |35 may be introduced to form a closed circuit through contact 99 and 10, serving to set the mechanism in operation by closing the circuit between source of potential indicated at |37 and the driving motor I3. The right hand portion |33 of the coin mechanism is pivoted at il and connected through bell crank 'l2 with rod I3 which is pivotally connected to lever 14 .controllable by cam B. As the lever 74 is moved to its extreme lower position at the end of the limit of travel of cam 8 and bringing the last characteristic reading into observation through aperture 8i, the coin |36 is released and the mechanism thus prepared for the next succeeding operation.

Shaft 3 opens the reagent dispensing apparatus through the operation of cams 9 and 9. Valve actuating rods i9 and 29 have their lower ends continuously urged into contact with cams 6 and 9 through springs 22 which normally tend to close the valves which admit the reagents to the test tubes 48 and 49.

'Ihe test performed on the fluid in test tube 49 differs from the test on the fluid in vtest tube 48 and, for this reason, the proportion of the iiuid and reagent necessarily differs. In order to make provision for the introduction into the test tube 49 of the precise quantity of fluid and reagent, I provide a measuring cup 25 connected through overflow tube 45 with central test tube 33 as shown. As the fluid overflows through tube 45, measuring cup 29 is filled. Cup 29 has a horizontally extending bottom partition 26a therein normally closed by a valve 25. Valve 25 is closed by means of valve rod 23 which passes through the lower chamber 2Gb. A coil spring 24 is provided for normally urging the valve 25 closed with respect to the valve seat in partition 25a of measuring cup 2S. Pressure is applied to spring 24 through piston member 2| operative in cylinder 2?. The coil spring 22 which is secured to Valve rod normally tends to urge piston 2| to the lowermost position in cylinder 21, allowing valve to open and deliver a predetermined quantity of test fluid through discharge pipe 3i? and spout 4l to test tube 49.

As cam 9 on shaft 3 is revolved by motor I3, rod 29 is raised, thereby moving piston 2| from a position normally closing port 29 in reagent tank |'l to the position illustrated in Fig. 7, in which the reagent may flow into the lower portion of cylinder 21. The lower p-art of cylinder 2 is closed by a valve 3 disposed on a horizontal axis in pipe line 3| and normally urged to closed position by coil spring 3l. As cam 9 is displaced angularly and rod 29 is allowed to move downwardly under the influence of coil spring 22, the reagent in cylinder 21 is forced against Valve 3| f displacing valve 3|' and allowing the reagent to be forced out through pipe 3|' and spout 41 Vand l.

stated, the arrangement of light source and light sensitive cell may be reversed as shown in Fig. 9.

The reagent supplied by tank Il to measuring cup 2i may be Benedicts solution for performing a test for sugar. Other reagents may be used.

In the test tube 48 the reagent is supplied from measuring cup i 4 from reagent reservoir I6 under control of a valve actuated by rod i9 under con-` trol of cam 9. The reagent may be acetic acid and Water for eifectinga test for albumen. The manner of operation of the valve 49 in the line leading to spout 46 is similar to the operation explained in connection with valve 3|".

A measuring cup similar to cup 26 may be provided abo-ve the cup I4 for receiving Water or other solution from an additional reservoir adjacent the reagent reservoirs I9 and I1 for'delivery to test tube 48 for securing a reaction with the y test fluid.

Y The insertion of a coin in slot y59 closes the electrical circuit to motor l 3 from source 31, thus initiating movement of the commutator drum I0 through the circuit arrangement illustrated more clearly in Fig. 4. The drum I9 carries contact segments 82, 9|?, 8l, 94, 99, w3, |95, i0! and95 onv adjacent insulated cylindrical portions of the drum, `whichportions I have indicated at 39, 85, 93, 99, 92, and 97. Sets of contacts are arranged adjacent the aforesaid cylindrical portions adapted to make sliding contact .with the contact segments in successive order. I have indicated insulated parts in each" of the cylindrical portions at 85., 89, 98, 93, 98, |02, and 91. The sets of contacts lead to different circuit elements, which contacts are slidably engaged peripherally with respect to the insulation parts and contact segments, heretofore described. That is, vthe conductive parts of the drum are the ring portions 92, 9|)y 81, 94, 99, |03, 95, 29| and |95, broken by suitable insulated parts 85, 85, 89, 93, 98, |02 and 9i.

The electron tube |44 has light sensitive cell 4i connected in its control circuit with' biasing means arranged to place the desired bias potential on the control grid through resistor |46. The output circuit of control tube |44 includes the meter 92 and source of potential |47. The circuit leading to the cathode of tube closed through leads 9E leading to contacts` 95 hrough the conductive portions 95, lili, and |95 of the druzn i9. Electrical connection is established through contacts 42 and 43, which arey electropositive and electronegative with respect to each other in the central test tube 93 through the set of contacts 9i, which connect to opposite terminals of meter 92. Contact |49 connects the heater coils 59 and 5l with the source of potential i3? for heating the test tubes 48 and 49 at the proper time interval. The light sources 49, 54 and 55 are energized at succeeding time intervals through contacts |4i, |42, and |43. It will be observed that these lamps are not put on simultaneously but successively so that different tests are performed at different time intervals as the drum I continues to revolve. The drum, when completely revolved at the conclusion of the several tests cuts off the circuit to the cathode and the circuit to the motor, at which time cam 1, as, shown in Fig. 8, has moved to a position where flush va1ve63'is opened admitting flush water to the pipe 62, which water is distributed from head 64 through spray aperturesiiE.` At the same time cams |30, |32 and 3| on shaft 3 actuate valve rods |48 for controlling bell cranks |49 and opening valves |50 in each of the test tubes 33, 48 and 49, -permitting flushing water introduced through spray apertures 65 to flood downwardly through the apparatus and out through discharge valves |50. The flushing operation may be traced through receptacle I', spout 34, through central test tube 33, discharge valve |50 to trough 60 through whichthe water is discharged through waste-pipe 6| to a sewerage connection. The waterfloods through tubes 44, 45, |5|, the water passing through discharge spout 46 into' test tube '25 48 and discharging through valve |50 for cleaning test tube 48 and passing into discharge trough 60. Water passes through pipes |5| and 45 clean- `ing cup 26and discharging through spout 41 to test tube 49 and discharge valve |50 to trough 60 through which it wastes through discharge pipe 6|.

The reel and web mechanism, for controlling the dry process of introducing the reagent, is illustrated in side view in Fig. 10 andin top plan view in Fig. 11 showing the reagent in dry form as embossed or printed on a transparent tape which is introduced into the liquid to be tested. Fig. 12 shows how the light sensitive cell may be sensitized by reflected light. Fig. 13 illustrates the manner in which the tape may be arrested momentarily when the reagent is centered in the test tube as shown by the employment of guide rollers.

The tape |06, bearing the reagent |01 deposited in charges at spaced intervals, is mounted on spool |08 and is made to pass over roller |09 downward to roller H0, thence to roller and around roller ||2 to motor driven spool ||3 on shaft H3 and wound thereon through sprocket wheels |4 and l5 by means of connecting chain 6. The shaft 3 supporting the driving sprocket ||5 is operated by induction motor |3 shown in Figs. 1 and 2. Meshing with roller I |2 is sprocket roller ||1 whose teeth ||8 are made to engage the perforations ||9 of the tape |06 for the purpose of moving the tape from spool |08. Adjacent to the roller ||1, supported on shaft |20, are brushes |2| contacting with commutator |22, peripherally supporting insulation block |23 and metallic block |24. Sprocket |25 on shaft |20 is engaged by chain |26 operably associated with sprocket |21 on shaft ||3', the arrangement operating to advance the tape |06 a predetermined distance. That is to say, the reagent is deposited in charges on the tape |06 at such distances as will equal one revolution of the sprocket roller ||1 when the shaft 3 effects a complete revolution thus centering, when properly adjusted, a charge of the reagent in the center of the test cup |34. The lamp |29 and the lens |30 serve as an optical systern for directing light rays on the light sensitive cell |3|, through lens |32. The heating coil |33 .similar to coils 50 and 5|, shown in Figs. 1 and 2, surround the test cup |34. Adjustable casing |35 which houses light sensitive cell 3| is screw threaded upon the lower portion of test' cup |34 as shown.

Fig. 12 shows the light sensitive cell 3| and the lamp |29 arranged in a modified optical systeml above the tape, the light sensitive cell being energized by light reflected from a mirrored spot such as a spot of aluminum paint, or otherwise, over which the reagent may be previously printed on the tape. The reagent on entering the test liquid dissolves and exposes the mirrored spot beneath, designated by the numeral |38, thereby serving as a reector. The turbid, cloudy solution effect or nepheloid characteristic indicated at 48', when it appears, obstructs the amount of light reflected to the light sensitive cell thereby correspondingly. controlling the operation of the meter 92.

Fig. 13 shows the commutator |22 carrying insulation block |23 and metallic block |24 in contacting engagement with brushes |2|, which brushes control the motor circuit through segment 82 shown in Fig. 4. The metallic block |24 servesto energize the lamp |29 in timed relation to the centering of the reagent |01 in the test cup |34. The gears |31 and |38 drive the commutator |22. The gears |31' and |38 are mutilated at a portion of their periphery to provide a momentary pause of the driven gear |31 occurring when the reagent reaches the center of the cup |34, at the instant of the lamp |29 being energized by the contact |22.

Another modified form of my invention includes registering meter |52, by which a permanent record of the test may be kept. Fig. l15 shows meter |52 having an extended shaft |53 to which is attached indicating needle |54. Interposed between the face of the meter and the elongated head |55, and operably associated with the armature |56 and free to be moved laterally, I provide a reel and web mechanism including a carbon backed tape |51. The indicating needle 54 carries at its upper end a projecting type pallet |58. The movement of the type pallet |58 describes an arc which covers the preprinted scale |59 on the tape |51 when such tape movement is centered with respect to shaft |53 by the roller |60. At a predetermined time, as the indicating needle |54 is influenced by the light sensitive cell 4| in the input circuit of amplier |6|, and the brushes |62 contact with metallic block |63, shown more clearly in Fig. 17 of the commutator |64, the electromagnet |65 becomes energized through source |65 causing the armature |56, carrying the elongated head 55 to be forced forward in opposition to spring |56'.

'Ihis forward stroke of the head |55 strikes the indicating needle |54 carrying the type pallet |58. The purpose of the elongated head is to encompass the entire scale range of the 1ndicating needle |54 so as to obtain an impress from the type pallet |58 of indicating needle |54 through the carbon back of the tape to provide a permanent mark through the tape, as shown at point |66 in Fig. 18. The predetermined travel of the tape is accomplished by a reel and web mechanism similar to that shown in Figs. 10 and 1l. The sprocket roller |60 is controlled by motor |3 through Worm |69, gear |10 on shaft |1l, gear |12 and gear |13. Fixed on shaft |1| is the commutator |64 having insulation block |15, contacting with brushes |62, |62', and |62". Brush |62" is not connected but indicates a continuation of the brush system. Brush |62" controls the motor circuit, as heretofore described,

tion with conductive contact segments ISI.

through coin |36 deposited in slot 68. Brush |62 controls the electromagnet |65 in connec- The meter |52 is controlled by brushes |62 in contacting with conductive contact segments |82 during the test period. The tape is advanced by teeth |84 on the sprocket roller |60 fitting into perforations |83 in the tape |51. The tape is mounted on roller |85 and drawn forward by sprocket roller itil and cooperative roller |86.

The advancement of the tape is eifected in timed relation to the several tests which are performed, so that a separate record card is delivered to the operator in a form shown in Fig. 18. The card has a scale, the rst portion of which reads Normal. Any movement of the indicating needle over this scale range under influence of the light sensitive cell will not indicate any abnormal condition of the test fluid. The movement of the indicator inthe normal range indicates that the reaction betweenthe reagent and the testl uid does not produce a turbid, cloudy or nepheloidal characteristic of an abnormal nature. The condition of the health may, therefore, be diagnosed. However, where a dangerous condition exists, the indicating needle moves over a scale range at |59 entitled See your physician, by reason of the action of the light sensitive cell in the optical system, due to the reflecting or obstruction of light rays with respect to the turbid, cloudy or nepheloidal characteristic produced by the reaction between the reagent and the test fluid. The scale of meter 92 in Fig. 3 is similarly calibrated, except that the scale divisions may be continuous from Normal through the scale range See your physician.

The proper time relation for the production of heat from coils Ellor |33 is essential in carrying out the method of my invention as heating is necessary to the production of the albumen and sugar tests of the test fluid. While the optical paths have been indicated as reflected from the reectors 56 and 51, other means may be employed for directing the light beams. I provide screens 58 and 58" in the optical paths to the light sensitive cell 4|' in order that a predetermined light intensity may be impressed upon the light sensitive cell 4|.

The method and structure of the apparatus as described herein, is to be considered as illustrative of one method and structure for carrying out the method of my invention and is not intended in the limiting sense, as I am aware that my invention may be embodied in modified methods and various structures may be employed in carrying out my invention. I intend no limitation upon my invention other than are imposed by the scope of the appended claims.

What I claim as new and desire to secure by Letters Patent of the United States is as follows:

1. An apparatus for testing the specific gravity of iiuid comprising a receptacle for receiving a quantity of the fluid to be tested, al hydrometer in said receptacle displaceable by the fluid under test, an indicator carried by said hydrometer and movable with respect to a light aperture, a light source on one side of said light aperture, a light sensitive cell on the other side of said light aperture, an electrically actuated indicator operated by said light sensitive cell, said iirst mentioned indicator operating to variably expose said light sensitive cell to the effects of said light source according to the displacement of said hydrometer for correspondingly indicating the specific gravity of said iiuid on said second mentioned indicator.

2. In an apparatus of theclass described, an electron tube circuit, a light sensitive cell connected to control the operation of said electron tube circuit, an indicating meter controlled by said electron tube circuit, a plurality of test tubes for receiving duid under test, light sources adjacent each of said test tubes and disposed in an optical path with respect to said light sensitive cell, electrical means for applying heat to each of said test tubes, means for depositing measured quantities of reagent in said test tubes, and switching means for selectively energizing said light sources in succession for taking observations of the character of the uid in each of said test tubes in successive order.

3. In an apparatus of the class described, an electron tube circuit, a light sensitive cell connected with said circuit, an indicating meter connected with said electron tube circuit, a plurality of test tubes for receiving fluid under test in combination with a reagent of predetermined characteristic, light sources individual to each of said test tubes for directing light rays through the fluid under test subsequent to the reaction thereof with the reagent, electrical means for heatingeach ofV said test tubes, and switching means for selectively energizing the light sources in succession for effecting independent readings of said meter under control of the light rays incident upon the combined test iiuid and reagent.

4. In an apparatus of the class described, a successively rellable receptacle, means for moving a tape through a test fluid in said receptacle, successive charges of reagent disposed at spaced intervals along said tape, said means for operating said first mentioned means simultaneously with a ushing operation in the receptacle preparatory to a refilling of the receptacle with the test fluid for effecting a chemical reaction with the test fluid, and optical and electrical means for determining the character of the reaction thus produced. Y l 5. In an apparatus of the class-described, a receptacle for receiving a test fluid, a driving motor, rotary mechanism operated by said motor, meansactuated by said rotary mechanism for introducing a measured quantity of test fluid into said receptacle, means actuated by said rotary mechanism for introducing a measured quantity of reagent into said receptacle, means controlled by said rotary mechanism for effecting an optical and electrical observation of the character of the reaction produced in said test tube, a valve in the base of said test tube, means actuated by said rotary mechanism for opening said valve and eecting a discharge of the solution therefrom, and means controlled by said rotary mechanism for subjecting saidV test tube to the iiow of cleaning medium subsequent to each test operation.

6. An apparatus of the class described, a oentral test tube, at least two auxiliary test tubes connected with said central test tube andadapted to receive measured quantities of test fluid overowing from said central test tube, means for introducing measured quantities of reagent into said auxiliary test tubes, means for optically and electrically determining the character of the reaction in said auxiliary test tubes, means for discharging the solution from all of said test tubes, and means operative subsequent to the .discharge of the solution from said test tubes for owing cleaning fluid through said central test tube and through each of said auxiliary test tubes preparatory to a succeeding test operation.

7. In an apparatus of the classdescribed, a coin controlled mechanism, rotary driving mech# anism adapted to be initiated in motion for a predeterminedY time interval under control of said coin control mechanism, a plurality of test tubes, means Vactuated by said rotary driving mechanism for delivering measured quantities of test fluid to said test tubes, separate means controlled by said driving mechanism for delivering 10 predetermined amounts of reagent to said test tubes, means for effecting different tests on the solution thus produced, an indicator actuated by said driving mechanism for visually indicating the character of each test, and means for making a printed record of the results of each test.

8. Inan apparatus of the class described, a light sensitive cell, an indicating meter controlled by said light sensitive cell, a plurality of test tubes for receiving fluid under test, a light source adjacenteach of said test tubes and disposedin anoptical path with respect to'said light sensitive cell, means for heating Neach of said test tubes, means for introducing measured ,quantities of reagent in each of said test tubes; and means for selectively energizing said light sources in succession for talringV observations 'of the'character of the fluid in each of the test n tubes in successive order. y o 9. In an apparatus of the class described, a receptacle for receiving a test fluid, a driving motor, Vrotary mechanism operated by said motor, means actuated by said rotary mechanism for introducing a measured quantity of test fluid D into said receptacle, means actuated by said rotary mechanism for introducing a measured quantity of reagent into said receptacle, means controlled by said rotary mechanism for effect- 40 ing Van optical and electrical observation of the character of the reaction produced in said test tube, means operated by said rotary mechanism for'eiectinga discharge of the solution from said test tube, and means controlledby said rotaryv mechanism for Vilushing said test tube subsequent to each test operation.

10. In an apparatus of the class described. a testing vessel, at least two auxiliary test tubes connected with said testing vessel, and adapted to receive measured quantities of test fluid overilowing from said testing vessel, means for introducing measured quantities of reagent into said auxiliary test tubes, means for optically and electrically determining the character of the predetermined time interval under control of said coin -controlleclmechanism,l a plurality of test tubes, means actuated-by said rotary driving Ymechanism fordelivering measured quantitiesof test fluid to'saidtest tubes,- separate means controlled-bysaid -drivingimechanism for deliveringpredetermined amounts of reagent i to saidltest tubesfmeans foreffectingdierent tests on the solutionthus-produced, and an' indicator actuated by said drivingmechanism-forvisually indicating the characterof Veach test;

l2.-In anapparatus ofthe-class described, a light sensitive cell, an indicatingmeter-controlledby said light sensitive cell-,a-p1urality of testtubes for receiving fluid under test, alight 3 source for projecting raysof'A 1ight-through each test tube in an optical path with respectl to -said light sensitive cell, means forA heating each-of saidtest tubes, means for introducing measured quantities of reagent in leachof said test tubes, and means for energizing saidv light source-for taking observations or the character of the fluid in each ofthe test tubes.

. JOfHN P. BUCKLEY. 

